JP4292400B2 - Disc cartridge - Google Patents

Description

  The present invention relates to a disk cartridge, and more particularly to a disk cartridge in which a shutter mounted so as to cover an opening of a casing so as to be openable and closable is opened and a disk in the casing is accessed through the opening.

  2. Description of the Related Art Optical disc players that perform signal writing or reading using a disc-shaped recording medium such as an optical disc are widely used. In order to protect the optical disc, a cartridge type in which the disc is housed in a casing has been proposed. In this case, a signal attached to or read from the casing is opened by opening a shutter attached to cover the opening of the casing so that the opening can be opened and closed, and the optical pickup accesses the disk in the casing through the opening. If the opening for access is left open, the disk is soiled or broken through the opening, so that the meaning of the cartridge type is lost. Therefore, the opening is covered with an openable shutter.

  In such a disk cartridge, for example, as disclosed in Japanese Patent Publication No. 7-89431, a disk is included in a substantially square case, and a shutter portion is provided with a restoring force of a torsion coil spring at a corner portion of the case. The member is moved to close the head insertion window, and the shutter member is engaged and held in this state by the lock means. Japanese Patent Application Laid-Open No. 2000-90634 discloses a magnetic tape cartridge biased so as to close the lid portion of the tape cartridge by a torsion coil spring.

  Here, the spring is used as the urging means for closing the shutter with the disc cartridge as described above. Especially when using a torsion coil spring as such a spring, if the stroke in the opening and closing direction of the shutter is large, the size when the spring opens will be large, and a spring requiring a large space will not fit in the casing. become. Therefore, as a countermeasure against such a problem, as disclosed in Japanese Patent Application Laid-Open No. 8-212750, the base end portion of the spring cartridge contacting the shell side can be moved within the shell, and a large stroke can be achieved in a narrow space. Attempts have been made to achieve.

However, even if such a structure is adopted, it is impossible to generate an urging force that urges the shutter in the direction in which it is stably closed over the entire stroke of opening and closing the shutter. That is, there is a problem that it is impossible to urge the shutter, which is housed in a small space and has a large opening / closing stroke, in the direction to be stably closed over all moving positions.
Japanese Patent Publication No. 7-89431 JP 2002-90634 A Japanese Patent Application Laid-Open No. 8-212750

  SUMMARY OF THE INVENTION An object of the present invention is to provide a disc cartridge capable of stably applying an urging force over the entire stroke of a shutter that covers an opening of a casing so as to be freely opened and closed.

  Another object of the present invention is to provide a disc cartridge having an urging mechanism that applies a stable urging force to a shutter in a narrow occupied space in a casing.

  Still another object of the present invention is to provide a disk cartridge having a torsion coil spring which is configured to apply a biasing force in a direction to be stably closed with respect to a shutter in a small occupied space.

  Still another object of the present invention is to maintain a stable urging force in a disk cartridge in which the opening of the casing is urged by a torsion coil spring so that the opening of the casing can be freely opened and closed, particularly at a position where the shutter closes the opening almost completely. It is an object of the present invention to provide a disk cartridge having a torsion coil spring.

  The above-described problems and other problems of the present application will be made clear by the technical idea and embodiments of the invention described below.

The main invention of the present application is a disc cartridge in which a shutter attached so as to freely open and close the opening of the casing is opened and the disc in the casing is accessed through the opening.
A locking member provided in the casing;
A locked portion provided in the shutter so that the shutter is locked by the locking member in a state where the opening is closed;
A release member attached to the shutter, and releasing the lock by the lock member of the locked portion of the shutter;
A spring that biases the shutter in a closing direction via the release member;
And the spring is composed of a torsion coil spring having a coil portion at an intermediate portion, and the coil portion of the torsion coil spring is pushed in the direction of closing the shutter by the inclined first wall portion of the casing, The base end portion of the torsion coil spring is pushed in the direction of closing the shutter by the inclined second wall portion of the casing, and the second wall portion pushes the shutter more than the portion in the direction of opening the shutter. The present invention relates to a disc cartridge characterized in that the portion closer to the closing direction has a larger inclination angle with respect to the stroke direction of the shutter.

  Here, the second wall portion that receives the base end portion of the torsion coil spring is formed of a curved surface, the inclination angle continuously changes with respect to the stroke direction of the shutter, and the portion on the direction side that closes the shutter. However, the inclination angle may be large. Further, the second wall portion that receives the base end portion of the torsion coil spring is composed of a plurality of linear wall surfaces having different angles, and the inclination angle changes stepwise with respect to the stroke direction of the shutter, The inclination angle may be larger in the portion on the closing direction side. The first wall portion may be provided closer to the opening than the second wall portion, and may have a wall surface that is inclined with respect to the opening / closing direction of the shutter. The torsion coil spring acts as a normal torsion coil spring until the shutter is moved from the opened state to the closing direction, and the base end portion of the torsion coil spring is almost at the end of the second wall portion. May be received. Further, the base end portion of the torsion coil spring may move on the second wall portion from the terminal end of the second wall portion in the middle of the transition from the opened state to the closing direction. Further, the first wall portion and the second wall portion may be constituted by ribs formed on the inner surface of the casing.

  According to a preferred aspect of the present invention, a base end portion that is in contact with a wall portion on the shell side of the shutter return spring and an end portion on the side opposite to the portion connected to the shutter moves along the cam shape of the shell. In the disk cartridge in which the return stroke of the shutter is enlarged, the return force of the shutter is stabilized by making the wall of the shell with which the base end of the spring abuts into a cam-shaped curve. is there.

  In particular, in the above aspect, in the disk cartridge in which the base end portion of the spring cartridge that urges the shutter in the closing direction is in contact with the wall surface on the housing side so as to be movable by the wall portion in the housing, The moving direction changes along the way. In particular, the angle formed by the moving path along the wall surface and the moving direction of the shutter is small on the side of the moving path far from the connecting portion with the shutter and large on the side near the connecting portion of the shutter.

  According to such an aspect, even in a disk cartridge having a large shutter stroke, it is possible to realize a shutter urging spring comprising a torsion coil spring having a small occupying space and a stable urging force. Such a shutter urging spring makes it possible to apply a sufficient urging force to the shutter even in its full stroke, particularly just before closing.

  The main invention of the present application is attached to the shutter, a lock member provided in the casing, a locked portion provided in the shutter so that the shutter is locked by the lock member with the opening closed. A torsion coil spring comprising: a release member that releases the lock of the locked portion of the shutter by the lock member; and a spring that biases the shutter in a direction to close the shutter via the release member, and the spring has a coil portion in the middle portion The coil portion of the torsion coil spring is pushed in the direction to close the shutter by the first wall portion inclined by the casing, and the base end portion of the torsion coil spring is shuttered by the second wall portion inclined by the casing. And the second wall portion is closer to the direction of closing the shutter than to the direction of opening the shutter. In which the inclination angle with respect to the stroke direction of the shutter is made larger.

  Therefore, according to such a disk cartridge, it is possible to set a large stroke for pushing the shutter with the torsion coil spring by the portion where the inclination angle of the second wall portion in the direction of opening the shutter is small. In addition, it is possible to generate a large urging force at a portion of the second wall portion where the angle on the side in which the shutter is closed is large. Therefore, particularly with the large urging force due to the large inclination angle portion, a sufficient urging force can be applied to the shutter even immediately before the shutter is closed, and the shutter is surely closed.

  The present invention will be described below with reference to embodiments shown in the drawings. FIG. 1 shows the overall structure of a disk cartridge according to the present embodiment. This disk cartridge includes a flat casing 10. That is, the casing 10 is composed of an upper shell 11 and a lower shell 12 made of synthetic resin that are joined from above and below. A circular center hole 13 through which the turntable enters is formed at a substantially central portion of the lower shell 12, and an access opening 14 extending to the side surface of the lower shell 12 is formed so as to be continuous with the center hole 13. ing. The optical pickup accesses the disk 65 accommodated therein through the access opening 14 while moving in the radial direction of the disk 65.

  A shutter 17 is attached so as to cover the center hole 13 and the access opening 14 of the lower shell 12 so as to be freely opened and closed. The shutter 17 further includes a release member 18 having a rod shape, and the shutter 17 is locked in a closed state by a lock plate 19 made of a leaf spring. The shutter 17 is urged in the closing direction by the torsion coil spring 20.

  Next, the structure of the upper shell 11 will be described with reference to FIGS. On the outer surface of the upper shell 11, that is, the upper surface, a label attaching recess 23 is formed. The upper shell 11 is formed with a coupling screw hole 24 for coupling to the lower shell 12. Further, a circular recess 25 is formed on the inner surface of the upper shell 11 as shown in FIG. Further, a locking groove 27 is formed on one side of the inner surface of the upper shell 11. The locking groove 27 is for receiving a locked portion 42 described later of the shutter 17.

  Next, the structure of the lower shell 12 will be described with reference to FIGS. A circular recess 30 is formed on the inner surface of the lower shell 12, and the disk 65 is held in the recess 30. A boss 31 is formed at a position corresponding to the coupling screw hole 24 of the upper shell 11, and a female screw hole 32 is formed at the center of the boss 31. Therefore, the upper and lower shells 11 and 12 are coupled to each other by assembling the casing 10 by screwing screws into the female screw holes 32 through the coupling screw holes 24 of the upper shell 11.

  A step 33 is formed on the side of the lower shell 12. The step portion 33 constitutes a sliding surface on which the release member 18 slides. A sliding recess 34 is formed on the lower surface of the lower shell 12, and the shutter 17 slides on the sliding recess 34 to open and close the access opening 14. Further, a deeper concave portion 35 is formed in the inner portion of the sliding concave portion 34. The recessed portion 35 receives the bent portion 44 on the distal end side of the shutter 17. A locking groove 36 is formed on the lower surface of the lower shell 12 and below the step 33. The locking groove 36 is configured to receive a locked portion 43 described later of the shutter 17.

  In addition, a first wall portion 71 made of a triangular rib is formed on the inner surface of the lower shell 12 and accommodates and holds the torsion coil spring 20, and the first wall A second wall portion 72 having a substantially arc shape is formed on the side portion of the portion 71 and at the corner portion of the lower shell 12. The second wall portion 72 receives the proximal end portion of the torsion coil spring 20, and the proximal end portion moves on the second wall portion 72, whereby the stroke of the shutter 17 in the closing direction is increased. The torsion coil spring 20 applies a stable biasing force to the shutter 17 over the entire range.

  Next, the shutter 17 that opens and closes the central hole 13 and the access opening 14 of the lower shell 12 of the casing 10 will be described. The shutter 17 is formed of a substantially rectangular metal plate as shown in FIGS. A side wall 38 bent at a right angle is formed on one end side in the length direction. A claw 39 is formed on the side end side of the side wall 38 so as to protrude in a direction substantially parallel to the main surface of the shutter 17. This claw 39 constitutes a locked part. A pair of holding pieces 40 are formed on the upper edge of the side wall 38. These holding pieces 40 are for holding the release member 18 sliding on the step portion 33 of the lower shell 12.

  Further, a pair of projecting pieces 41 are formed at the upper end of the side wall 38 of the shutter 17 of the shutter 17, and a locked portion 42 is formed at a tip side portion of these projecting pieces 41 so as to project upward. . The locked portion 42 is engaged with a locking groove 27 formed on the inner surface of the upper shell 11, thereby preventing the shutter 17 from falling off the casing 10. Furthermore, a locked portion 43 is formed at the side end of the side wall 38 opposite to the claw 39, and the locked portion 43 is engaged with the locking groove 36 on the lower surface of the lower shell 12 so that the shutter 17 is moved. This prevents the casing 10 from falling off. Further, a bent portion 44 is formed at an end portion of the shutter 17 opposite to the end portion where the side wall 38 is formed, and the bent portion 44 is received in the deep concave portion 35 on the lower surface of the lower shell 12. This prevents the tip of the shutter 17 where the bent portion 44 is formed from being caught by foreign matter or the like.

  Next, the release member 18 that slides on the step portion 33 of the lower shell 12 while being held inside the side wall 38 of the shutter 17 will be described with reference to FIGS. The release member 18 has a recess 47 at its side end. A cam 48 is formed at one end of the recess 47 and at the left end side in FIGS. A through hole 49 is formed in the release member 18 in the lateral direction so as to open to the recess 47. The claw 39 of the shutter 17 is inserted through the through hole 49. A step portion 50 is formed on the back side of the through hole 49 and on the back side of the release member 18.

  Further, a step 51 is formed at the end of the release member 18 opposite to the portion where the through hole 49 is formed. A cut 52 is formed in the step portion 51, and a connecting portion 53 is formed so as to cross the cut 52, and the inside of the connecting portion 53 is an engagement hole 54. The engagement hole 54 receives the bent portion 63 at one end of the torsion coil spring 20.

  Next, the lock plate 19 for locking the shutter 17 will be described. As shown in FIGS. 17 to 19, the lock plate 19 is bent into a substantially U shape by an elongated plate spring, and protrudes upward and downward from a portion on one end side of the plate spring 19. A protrusion 57 is formed. These protrusions 57 are held by the upper shell 11 and the lower shell 12, thereby holding the leaf spring 19 at a predetermined position inside the casing 10. In addition, a horizontally long lock hole 58 is formed at a substantially intermediate position in the length direction of the leaf spring 19 and in the vicinity of the bent-shaped bent portion. A substantially horizontal receiving surface 59 is formed at the end of the leaf spring 19 opposite to the end where the protrusion 57 is formed. The receiving surface 59 comes into contact with the wall surface of the lower shell 12.

  Next, the torsion coil spring 20 that biases the shutter 17 in the closing direction will be described with reference to FIGS. The torsion coil spring 20 is formed by winding an elongated wire having a circular cross section, and both ends thereof are provided with arms extending in opposite directions to each other, and bent portions are provided at the distal end side portions of the arms extending left and right. 62 and 63 are formed. One of the bent portions 62, 63 of these arms is received by the concave portion of the shell 12, and the other bent portion 63 is engaged with the engagement hole 54 of the release member 18. .

  Next, the locking mechanism of such a disk cartridge will be described with reference to FIG. The lock mechanism of the shutter 17 includes a claw 39 provided in the shutter 17, a release member 18 having a through hole 49 through which the claw 39 is inserted, and a lock plate 19 formed of a leaf spring. The release member 18 is assembled inside the side wall 38 of the shutter 17 while being held by the side wall 38 of the shutter 17 and the holding piece 40 on the step portion 33 of the lower shell 12. At this time, the claw 39 of the shutter 17 is inserted into the through hole 49 of the release member 18, and the tip of the claw 39 protrudes from the through hole 49 and engages with the lock hole 58 of the lock plate 19. Locking is performed.

  FIG. 24A shows a state in which the claw 39 of the shutter 17 is engaged with one edge of the lock hole 58 of the lock plate 19 and the shutter 17 is thereby locked. At this time, the claw 39 is in contact with the lower side wall portion of the through hole 49 of the release member 18. That is, in the locked state, the release member 18 moves relative to the shutter 17 in the direction in which the shutter 17 is closed, that is, upward in FIG. 23A.

  In such a locked state, as shown in FIG. 24B, the release member 18 is slid relative to the shutter 17 in the unlocking direction, that is, in the direction in which the shutter 17 is opened. At this time, the release member 18 moves downward in FIG. 24B with respect to the shutter 17 by the clearance between the dimension in the stroke direction of the through hole 49 of the release member 18 and the dimension in the same direction of the claw 39. At this time, the cam 48 on the upper end side of the recess 47 of the release member 18 pushes the lock plate 19 and pushes the lock plate 19 leftward in FIG. That is, the movement of the release member 18 in the unlocking direction causes the lock hole 58 of the lock plate 19 to move laterally away from the claw 39, so that the tip portion protruding from the through hole 49 of the claw 39 is the lock plate 19. Relatively disengage from the lock hole 58. As a result, the unlocking operation is performed.

  The locking operation is achieved by moving the release member 18 in the closing direction of the shutter 17, that is, upward in FIG. When the release member 18 is moved in the same direction, the release member 18 and the shutter 17 coupled via the claw 39 move together. Eventually, the claw 39 of the shutter 17 is moved to the release member 18 as shown in FIG. 24A. The locking is performed by engaging with the lock hole 58 of the leaf spring 19 dropped into the recess 47 of the plate.

  25 and 26 show a state in which the shutter 17 closes the center hole 13 and the access opening 14 of the lower shell 12 of the casing 10. Here, the casing 10 is shown with its upper shell 11 removed, and only the lower shell 12 is shown here. A disk 65 is accommodated in the circular recess 30 of the lower shell 12, and the shutter 17 closes the center hole 13 and the access opening 14. The claw 39 of the shutter 17 passes through the through hole 49 of the release member 18 and enters the lock hole 58 of the lock plate 19. The lock plate 19 is in a state in which the projection 57 at one end thereof is held and fixed in the recesses of the upper shell 11 and the lower shell 12.

  Here, even if the shutter 17 is moved leftward in FIGS. 25 and 26, the claw 39 of the shutter 17 is caught by the edge of the lock hole 58 of the lock plate 19 and the shutter 17 is not moved in the opening direction. As described above, the release member 18 is provided in the shutter 17, and the claw 39 of the shutter 17 is inserted into the through hole 49. A concave portion 47 having a cam 48 is formed on a side portion of the release member 18, and a lock plate 19 bent in a U-shape is inserted into the concave portion 47. The torsion coil spring 20 is pushed rightward in FIGS. 25 and 26 in the direction of closing the shutter 17 via the release member 18. The left side wall portion of the through hole 49 of the release member 18 pushes the shutter 17 by the claw 39 of the shutter 17, and for this purpose, the shutter 17 abuts against the contact step 66 (see FIG. 26) of the lower shell 12 and closes. Holding. This is a state where the shutter 17 is closed and locked.

  In contrast, FIGS. 27 and 28 show a state in which the shutter 17 completely opens the center hole 13 and the access opening 14 of the lower shell 12 of the casing 10. When the release member 18 is pushed in the direction in which the shutter 17 is opened by a member not shown, that is, leftward in FIGS. 27 and 28, the shutter 17 is unlocked, and the release member 18 passes the claw 39 of the shutter 17 through the through hole. Push it on the right wall of 49 and move it to the left.

  In the state where the shutter 17 is fully opened, the torsion coil spring 20 directly pushes the left side edge on the side wall 38 side of the shutter 17 as shown in FIG. Is in a state. Such a structure eliminates the need for applying a force by the torsion coil spring 20 to the release member 18 made of a plastic part, and can thereby more reliably prevent the release member 18 from being deformed in a high temperature environment. become.

  As described above, the torsion coil spring 20 that closes the shutter 17 has the coil portion 61 at its intermediate portion, and both ends are bent portions 62 and 63. The coil portion 16 of the torsion coil spring 20 is in contact with the first wall portion 71 of the lower shell 12, and the bent portion 62 is in contact with the oblique second wall portion 72 of the lower shell 12 (FIG. 29).

  Here, when the shutter 17 transitions from the opened state to the closed state, the torsion coil spring 20 acts as a normal torsion coil spring and urges the shutter 17 in the closing direction until the middle of the stroke. However, after the stroke, the coil portion 61 of the torsion coil spring 20 is in contact with the first wall portion 71 of the lower shell 12, and the bent portion 62 on the base end side of the torsion coil spring 20 is in contact with the lower shell 12. By moving diagonally along the second wall surface 72, the shutter 17 is biased in the closing direction.

  At this time, when the urging force of the torsion coil spring 20 that urges the shutter 17 in the closing direction is obtained, it is as shown in FIG. In the graph of this figure, the horizontal axis indicates the stroke of the shutter 17, and it moves in the closing direction as it goes to the right. On the other hand, the vertical axis indicates the biasing force of the torsion coil spring 20. As is apparent from this graph, in the second half mode in the closing direction, the biasing force of the torsion coil spring 20 against the shutter 17 is very small, especially when the stroke required to close the shutter 17 is long, the vicinity of the end of this stroke. The energizing force at is very small. Then, there is a possibility that the shutter 17 cannot be reliably closed.

  In the second mode of the torsion coil spring 20, that is, in a state where the coil portion 61 of the torsion coil spring 20 contacts the first wall portion 71 and the bent portion 62 moves along the second wall portion 72. In order to increase the biasing force of the spring 20, the angle formed between the second wall portion 72 along which the bent portion 62 of the torsion coil spring 20 moves and the moving direction of the shutter 17 may be increased. For example, FIG. 31 shows a state in which this angle is larger than that in FIG. However, when the angle of the second wall portion 72 is increased with respect to the moving direction of the shutter 17, the bent portion 62 of the torsion coil spring 20 is swung when the moving stroke of the shutter 17 exceeds a certain value. That is, if the angle of the second wall portion 72 is increased, the stroke of the shutter 17 cannot be increased. FIG. 32 shows the change in the biasing force of the torsion coil spring 20 when the angle of the second wall 72 is increased.

  In order for the torsion coil spring 20 to operate effectively even if the stroke in the closing direction of the shutter 17 is increased, the shutter 17 of the second wall 72 moves along the bent portion 62 of the torsion coil spring 20. The angle with respect to the stroke direction may be reduced as shown in FIG. However, if the angle of the second wall portion 72 is reduced as shown in FIG. 33, the urging force of the torsion coil spring 20 against the shutter 17 is reduced as shown in FIG.

  Therefore, in the present embodiment, as shown in FIG. 35, the shape of the second wall portion 72 of the lower shell 12 is curved, and the angle of the second wall portion 72 with respect to the stroke direction of the shutter 17 is set to the shutter 17. In the shape opposite to the closing direction of the shutter 17, the size is reduced, and on the closing direction side of the shutter 17, the shape is increased. That is, as shown in FIG. 35, it has a substantially circular arc shape, and the angle of the second wall 72 is gradually increased toward the side closer to the shutter 17 in the stroke direction.

  FIG. 36 shows a change in the urging force of the torsion coil spring 20 having such a configuration. In particular, in the case of the structure shown in FIG. 35, the second wall 72 has a small stroke at a portion of the second wall 72 opposite to the closing direction of the shutter 17 and a small inclination angle. The torsion coil spring 20 applies a high urging force to the shutter 17 immediately before the shutter 17 closes due to a large angle at the end of the shutter 17 in the closing direction.

  That is, in this embodiment, the force of the torsion coil spring 20 that biases the shutter 17 in the closing direction is changed as shown in FIG. 36 by the configuration shown in FIG. In the first half of the stroke of the second mode in which the urging force has a margin, the angle of the second wall 72 is reduced, thereby increasing the stroke of the torsion coil spring 20 with respect to the shutter 17 and the second wall 72. In particular, in the latter half, that is, the portion on the side where the shutter 17 is closed, the angle is increased to prevent the urging force from being lowered. Therefore, a large urging force can be obtained over a long stroke in the opening / closing direction of the shutter 17.

  Next, another embodiment will be described with reference to FIG. In this embodiment, the shape of the second wall portion 72 of the lower shell 12 in contact with the bent portion 62 of the torsion coil spring 20 that urges the shutter 17 is compared in the portion opposite to the closing direction of the shutter 17. A linear wall portion having a small target angle is formed, and an arc-shaped wall portion is provided so as to be continuous with the linear wall portion, and these are continuously formed as a wall portion 72. Therefore, in this case, the latter half portion has the same shape as that of the first embodiment, but the first half portion is formed of a linear wall portion having a small angle. Even with such a configuration, it is possible to achieve substantially the same operational effects as the above-described embodiment.

  FIG. 48 shows still another embodiment. In this embodiment, the shape of the second wall portion 72 of the lower shell 12 in contact with the bent portion 62 on the shell side of the torsion coil spring 20 is constituted by two linear portions. That is, the first half portion of the second wall portion 72 is constituted by a small-angle wall portion, and the latter half portion is constituted by a large-angle wall portion, and these are continuous to form the second wall portion 72.

  According to such a configuration, a long stroke is secured by the torsion coil spring 20 at the beginning of the small inclination angle, and the torsion coil spring 20 applies a large biasing force to the shutter 17 by the wall portion having the large inclination angle in the latter half. Enable.

  As described above, the disk cartridge according to the present embodiment and the modified example is an end portion on the opposite side to the end portion connected to the shutter 17 of the torsion coil spring 20 that biases the shutter 17 in the closing direction, and the bent portion 62. In the disk cartridge in which the return stroke of the shutter 17 is expanded by moving the end portion where the head is formed along the cam-shaped wall portion 72 of the lower shell 12, the shape of the second wall portion 72 is changed. By devising, the torsion coil spring 20 can secure a large stroke and stabilize the return force applied to the shutter 17. Therefore, even in a disk cartridge in which the stroke of the shutter 17 in the opening / closing direction is large, a disk cartridge having a torsion coil spring 20 that generates a stable urging force in a small occupied space in the lower shell 12 can be provided.

  The present invention can be widely used as a cartridge type recording medium of an optical disk player for writing or reading a signal by the optical disk player.

It is an exploded perspective view of a disk cartridge. It is a top view of an upper shell. It is a bottom view of an upper shell. It is a front view of an upper shell. It is a top view of a lower shell. It is a bottom view of a lower shell. It is a front view of a lower shell. It is the sectional view on the AA line in FIG. It is a top view of a shutter. It is a front view of a shutter. It is a side view of a shutter. It is a perspective view of a shutter. It is a principal part expansion perspective view of a shutter. It is a top view of a cancellation | release member. It is a front view of a cancellation | release member. It is a perspective view of a cancellation | release member. It is a top view of a lock board. It is a front view of a lock board. It is a perspective view of a lock board. It is a top view of a torsion spring. It is a front view of a torsion spring. It is a perspective view of a torsion spring. It is a disassembled perspective view of the locking mechanism of a shutter. It is a principal part top view of the locked state and unlocked state of a shutter. FIG. 3 is a plan view of the disk cartridge with the shutter closed. FIG. 3 is a front view of the disc cartridge with the shutter closed. FIG. 3 is a plan view of the disc cartridge with the shutter opened. FIG. 3 is a front view of the disk cartridge with the shutter opened. It is a principal part top view which shows the relationship between the wall part formed in a lower shell, and a torsion coil spring. It is a graph which shows the change of the urging | biasing force of a torsion coil spring. It is a top view similar to FIG. 29 when the angle of the 2nd wall part of a lower shell is enlarged. It is a graph which shows the change of the urging | biasing force of a torsion coil spring. It is a top view similar to FIG. 29 when the angle of the 2nd wall part of a lower shell is made small. It is a graph which shows the change of the urging | biasing force of a torsion coil spring. It is a top view similar to FIG. 29 when the 2nd wall part of a lower shell is made into circular arc shape. It is a graph which shows the change of the urging | biasing force of a torsion coil spring. It is a top view which shows the relationship between the torsion coil spring of a modification, and the wall part of a lower shell. It is a graph which shows the relationship between the torsion coil spring of another modification, and the wall part of a lower shell.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Casing, 11 ... Upper shell, 12 ... Lower shell, 13 ... Center hole, 14 ... Access opening, 17 ... Shutter, 18 ... Release member, 19 ... Lock plate (leaf spring) , 20 torsion coil springs, 23 recesses for attaching labels, 24 screw holes for coupling, 25 circular recesses, 27 locking grooves, 30 circular recesses, 31 bosses, 32 ... Female threaded hole, 33 ... Step part, 34 ... Sliding recess, 35 ... Deep recess, 36 ... Locking groove, 38 ... Side wall, 39 ... Claw, 40 ... Holding piece, 41 ... ... Projection piece, 42, 43 ... Locked part, 44 ... Bending part, 47 ... Recess, 48 ... Cam, 49 ... Through hole, 50, 51 ... Step part, 52 ... Notch, 53 ····················································································· 58 2,63 ‥‥ bent portion, 65 ‥‥ disk, 66 ‥‥ those Seddan unit, 71 first wall portion ‥‥, 72 ‥‥ second wall

Claims (7)

In a disc cartridge that opens a shutter attached to cover the opening of the casing so as to be openable and closable, and accesses the disc in the casing through the opening.
A locking member provided in the casing;
A locked portion provided in the shutter so that the shutter is locked by the locking member in a state where the opening is closed;
A release member attached to the shutter, and releasing the lock by the lock member of the locked portion of the shutter;
A spring that biases the shutter in a closing direction via the release member;
And the spring is composed of a torsion coil spring having a coil portion at an intermediate portion, and the coil portion of the torsion coil spring is pushed in the direction of closing the shutter by the inclined first wall portion of the casing, The base end portion of the torsion coil spring is pushed in the direction of closing the shutter by the inclined second wall portion of the casing, and the second wall portion pushes the shutter more than the portion in the direction of opening the shutter. 2. A disk cartridge according to claim 1, wherein a portion closer to the closing direction has a larger inclination angle with respect to the stroke direction of the shutter.
  The second wall portion that receives the base end portion of the torsion coil spring is formed of a curved surface, the inclination angle continuously changes with respect to the stroke direction of the shutter, and the portion on the direction side that closes the shutter is inclined. 2. The disk cartridge according to claim 1, wherein a corner is large.   The second wall portion that receives the base end portion of the torsion coil spring is composed of a plurality of linear wall surfaces having different angles, the inclination angle changes stepwise with respect to the stroke direction of the shutter, and the shutter is closed. 2. The disk cartridge according to claim 1, wherein the direction side portion has a larger inclination angle.   2. The disk cartridge according to claim 1, wherein the first wall portion is provided closer to the opening than the second wall portion, and has a wall surface that is inclined with respect to an opening / closing direction of the shutter. .   The torsion coil spring acts as a normal torsion coil spring until the shutter is moved from the opened state to the closing direction, and the base end portion of the torsion coil spring is received at the almost end of the second wall portion. The disc cartridge according to claim 1, wherein the disc cartridge is used.   The proximal end portion of the torsion coil spring moves on the second wall portion from the end of the second wall portion in the middle of the transition from the opened state to the closing direction. The disc cartridge according to claim 5. 2. The disk cartridge according to claim 1, wherein the first wall portion and the second wall portion are configured by ribs formed on an inner surface of the casing.

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